[ccp4bb]: MOSFLM Warning

[Ricardo Aparicio <aparicio@if.sc.usp.br>]

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Dear all,

I am getting the crystal slippage warning message (bellow) when integrating a data set 
collected at 100 K. I have seen it before but this time I can't solve it.

Rmerge values for partials and fulls are similar, no weird behavior.
All the parameters plots seems OK.
Crystal was correctly centered in the beam and mosaicity value seems to be OK.
I would like some help:

- to find the probable cause for this message
- to solve the problem.

Also, the message says that
"
There may be serious errors in the intensities of partially recorded
  reflections. This can be checked by merging only fully recorded reflections
  in SCALA/AGROVATA
"
How to check it in SCALA ? I mean, to merge only fully and compare what? The very 
intensities themselves?


Should I worry about this message?


Your help is very welcomed.

Many thanks,

Ricardo Aparicio
IFSC-USP/Brazil


*** Warning messages ***

  CRYSTAL SLIPPAGE
  ================
  There is significant slippage between successive images
  (Maximum slippage is    0.13 degrees which is more than a quarter of the sum
  of the beam divergence and mosaic spread.
  There may be serious errors in the intensities of partially recorded
  reflections. This can be checked by merging only fully recorded reflections
  in SCALA/AGROVATA. In extreme cases it may be helpful to increase the
  mosaic spread or beam divergence parameters to improve processing.